Advanced Composite Materials: Properties and Applications

Composite materials are a major growth area within advanced materials and the range of applications for such products continues to grow and increase in diversity with every new development. Composite products are highly in demand and reached sales of $21.2 billion globally in 2014. The top three market segments in 2014 were transportation, construction, pipes, and tanks. Other segments include energy, automotive, and aerospace. This state-of-the-art book has been written by high-profile authors who have extensive experience and knowledge in the field of composite materials. The chapters in this collection would be useful for a wide range of audience: undergraduate and post-graduate students students, industrial professionals, materials scientists and researchers, and composite manufacturers. This book provides the reader with a wide range of information in the interdisciplinary subject area of composite materials. The book consists of thirteen chapters. It deals with two types of nanocomposites: graphene and carbon nanotube reinforced nanocomposites, their manufacturing, properties and applications. It also presents fibre reinforced composites and a comprehensive review of bio-composites. Furthurmore, it has a focus on thermal, mechanical and electrical properties of advanced composite materials

A novel method to investigate the polystyrene nanofiber formation during electrospinning process

In this study, the formation of polystyrene (PS) nanofibers during electrospinning process was investigated using a simple coagulation method. The fiber diameter, bead size and bead density of the PS nanofibers electrospun from the solutions with three different PS concentrations were studied. It revealed that the initial stage of electrospinning was responsible for fiber thinning, while the later stage is responsible for improving the fiber uniformity

Fabrication, characterization and modeling of functionally graded synthetic graphite/polymer nanocomposites

In this chapter, the fabrication, characterization, and modeling of functionally graded nanocomposites (FGNs) are presented. FGNs with phenolic matrix and synthetic graphite (SG) as nanofillers were fabricated using a combined powder stacking and compression molding techniques. Ball milling was used to homogeneously distribute nanofillers within the phenolic matrix. The process allowed FGNs with four different microstructure gradient patterns of the same geometry and SG content, as well as non-graded nanocomposites (NGNs), to be fabricated. The surface morphology of FGNs and SG distribution were examined. The transient thermal behavior of FGNs subjected to sudden temperature changes was numerically investigated to examine the effect of compositional patterns on the temperature gradient field in these materials. Temperature-dependent thermal conductivity and heat capacity of the FGN components were measured and used in finite element-based transient thermal analysis developed based on the experimental procedure. A controlled microstructure and composition was achieved in microscale. Thermomechanical and viscoelastic properties of nanocomposites were highly affected by the distribution patterns of SG within the matrix. The transient thermal analysis results showed that the transient time and temperature field in nanocomposite structures were highly influenced by the compositional gradient configurations. The FGN with a gradual decrease in reinforcing content from the exposed side to the other side had the lowest temperature gradient field (about 11 °C less than the other gradient patterns) and transient time (about 56 seconds less than the other gradient patterns)

Fabrication, characterization and modelling of functionally graded nanocomposites

This research introduced the innovative concept of controlling the composition in nanocomposites for optimizing the mechanical performance; as well as tailoring the thermal and electrical properties for multi-functional applications. It led to the development of novel lighter stronger materials for use in engineering applications such as automotive body and mining equipment

Transient temperature distribution in functionally graded graphite/Polymer nanocomposites based on temperature dependent properties

Transient heat conduction in a functionally graded graphite/polymer nanocomposite (FGN) plate is analyzed using finite element method (FEM). Stepwise gradient structure consisted of four different nanocomposite layers with 0, 5, 10 and 20 wt% of graphite. Thermal conductivity and specific heat capacity of the individual layers were determined using C-Therm TCi Thermal Conductivity Analyzer (Canada) in temperature range of -20 to 100 &deg;C. Temperature history and temperature distribution across the thickness of the plate with two different configurations for two positive and negative temperature gradients are presented. <br /

Functionally graded carbon nanofiber/phenolic nanocomposites and their mechanical properties

For the first time, functionally graded carbon nanofiber/phenolic nanocomposites were designed and fabricated. The effect of compositional gradients on the flexural properties of functionally graded carbon nanofiber/phenolic composite beams was evaluated. Samples with four compositional gradients as well as a non-graded nanocomposite with the same total carbon nanofiber content and geometry were fabricated using a combination of powder stacking and compression molding techniques. Analytical and finite element models were both performed to investigate the effects of compositional gradients, boundary conditions, and external loadings on flexural properties of nanocomposite beams. Close agreement was observed between analytical solutions, finite element analyses and experiment. The morphology of the fracture surfaces was examined using a scanning electron microscope. The results showed that the flexural properties of carbon nanofiber/phenolic nanocomposites can be greatly improved by controlling the carbon nanofiber content across the thickness of the samples

Structure-property relationships in nylon 6 nanocomposites based on octaphenyl-, dodecaphenyl-POSS, montmorillonite, and their combinations

Binary and ternary nanocomposites were produced by incorporating, via melt compounding, two types of octa-and dodecaphenyl substituted polyhedral oligomeric silsesquioxanes (POSS), montmorillonite (MMT), and combinations of POSS with MMT into nylon 6. The tensile, flexural, and dynamic thermo-mechanical properties of these materials were characterized and their structure-property relationships discussed. The results show that the losses in ductility and toughness experienced after inclusion of MMT into nylon 6 can be balanced out by co-mixing MMT with the dodecaphenyl- POSS to produce a ternary nanocomposite. This trend however was less pronounced in the ternary MMT/octaphenyl-POSS system. Analysis of the microstructure organization in these materials using XRD and SEM sheds some light on understanding the differences in behavior. Both types of POSS particles mixed alone in nylon 6 were found to be polydisperse (500 nm to a few microns in size) and locally aggregated, yielding materials with similar mechanical performance. The co-mixing of MMT with the octaphenyl- POSS served to break down the POSS crystal aggregates, enhancing their micro-mechanical reinforcing action. On the other hand, the POSS crystals were not affected in the MMT/dodecaphenyl-POSS system, which led to improving their toughening ability

Preparation and properties of composition-controlled carbon nanofiber/phenolic nanocomposites

Composition-controlled carbon nanofiber/phenolic nanocomposites were designed and fabricated using a combination of powder stacking and compression molding techniques. The microstructure and composition distribution were evaluated. Experiments showed that their thermomechanical and viscoelastic properties were highly influenced by compositional gradient patterns of the nanocomposites. Electrical and thermal properties were able to be controlled from the surface to the core of the nanocomposites

Fabrication and characterization of functionally graded synthetic graphite/phenolic nanocomposites

Stepwise functionally graded synthetic graphite/phenolic nanocomposites (FGNs) were fabricated using combined powder stacking and compression molding techniques. The process allowed the fabrication of FGNs with four different microstructure gradient patterns of the same geometry and graphite content, as well as non-graded nanocomposites (NGNs). The FGN with the highest graphite content layer on the top and bottom surfaces and the lowest in the center, showed the highest improvement of 97% in thermo-mechanical properties and the best creep recovery of 34.7% among all FGNs and NGN. Introducing graphite by 20. wt% increased thermal conductivity of phenolic from 0.35 to 0.88. W/(m °C) and decreased its electrical resistivity to 20.8 Ω/cm. It was found that the electrical and thermal properties of nanocomposites could be manipulated by changing the gradient patterns

A novel carbon nanofibre/phenolic nanocomposite coated polymer system for tailoring thermal behaviour

Carbon nanofibre (CNF)/phenolic nanocomposite coatings were applied to the phenolic substrate for tailoring thermal behaviour under rapid temperature changes. A finite element (FE) model was developed in this work for transient thermal analysis of coated samples. The effects of thickness and CNF content of the CNF/phenolic nanocomposite coating on reducing temperature gradient field within the samples as well as transient time to steady state were investigated. Temperature-dependent thermal properties including thermal conductivity and heat capacity of phenolic and its nanocomposites containing 2, 4 and 16 wt% CNF were experimentally determined and employed in the FE analysis. The results showed that the temperature gradient field and transient time within the polymers can significantly be decreased by using a CNF/phenolic nanocomposite coating